Inheriting a Tenant

[Account Closed]

I just got my first property under contract, it's the first property I've ever purchased including primary residence. It's a 2 unit building and I'm moving into one and renting the other. 

The sellers agent says the current tenant isn't in a lease and pays monthly rent between $1100 to $1200.

Im approaching this tenant for the first time. I want to raise rents and ask him/her to sign a lease. The market indicates I can get about $1300 for this unit.  

Is there a way to do this without ruffling feathers? Any advice is appreciated.